首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   636篇
  免费   30篇
  国内免费   4篇
耳鼻咽喉   4篇
儿科学   17篇
妇产科学   8篇
基础医学   95篇
口腔科学   16篇
临床医学   34篇
内科学   190篇
皮肤病学   12篇
神经病学   26篇
特种医学   18篇
外科学   71篇
综合类   2篇
预防医学   80篇
眼科学   4篇
药学   29篇
中国医学   2篇
肿瘤学   62篇
  2023年   12篇
  2022年   8篇
  2021年   14篇
  2020年   12篇
  2019年   14篇
  2018年   18篇
  2017年   9篇
  2016年   13篇
  2015年   15篇
  2014年   18篇
  2013年   29篇
  2012年   51篇
  2011年   48篇
  2010年   28篇
  2009年   22篇
  2008年   33篇
  2007年   60篇
  2006年   41篇
  2005年   45篇
  2004年   44篇
  2003年   23篇
  2002年   32篇
  2001年   11篇
  2000年   5篇
  1999年   6篇
  1998年   6篇
  1997年   11篇
  1996年   7篇
  1995年   3篇
  1994年   7篇
  1993年   1篇
  1992年   1篇
  1991年   2篇
  1990年   1篇
  1989年   2篇
  1988年   4篇
  1987年   1篇
  1986年   3篇
  1985年   2篇
  1984年   1篇
  1982年   2篇
  1981年   1篇
  1980年   1篇
  1979年   2篇
  1961年   1篇
排序方式: 共有670条查询结果,搜索用时 15 毫秒
51.
The human gamma-aminobutyric acid type B (GABA(B)) receptor gene is a candidate gene for schizophrenia due to its chromosomal location and neurobiologic roles. In the present study, association analyses of genetic polymorphisms of the GABA(B) receptor gene with schizophrenia were carried out in 102 unrelated schizophrenic patients and 100 healthy controls, using a polymerase chain reaction-based, single-strand conformational polymorphism analysis. Although the Ala20Val and Gly489Ser mutations were not found in our samples, we found a novel polymorphism of (AC)n dinucleotide repeats located approximately 1.6 kb upstream from the translational start site. No significant difference in allele frequencies was found between controls and patients with schizophrenia (P = 0.0587) using the Monte Carlo method. Significant differences were found between controls and patients with continuous-course schizophrenia (P = 0.0019), and between controls and patients with a positive family history of psychoses (P = 0.0015). These differences, however, were not significant after Bonferroni correction. These data did not support our hypothesis that polymorphisms of the GABA(B) receptor gene may confer vulnerability for schizophrenia.  相似文献   
52.
PURPOSE: To evaluate three-dimensional (3D) constructive interference in steady-state (CISS) magnetic resonance (MR) imaging and MR angiography with multiplanar reconstruction (MPR) for detection of neurovascular compression (NVC) in patients with trigeminal neuralgia and to evaluate the relationship between clinical symptoms related to trigeminal branches and those related to the site of trigeminal nerve compression. MATERIALS AND METHODS: Fifty-four consecutive patients with trigeminal neuralgia were examined at 3D CISS imaging and MR angiography with a 1.5-T MR system. Original transverse and four reformatted images were used for image interpretation. Vascular contact with the trigeminal nerve at the root entry zone (REZ) was determined, and the nature of the involved vessels was identified. The position of the blood vessel compressing the nerve was classified into cranial, caudal, medial, or lateral sites. Statistical analysis was performed with the chi2 test or the Fisher exact test between two groups and with the chi2 test among more than two groups. RESULTS: In 12 of 15 patients who underwent surgery, the artery that was considered a responsible vessel at 3D CISS imaging and MR angiography was confirmed as such. In the other three patients, the vein was the responsible vessel, which was detected only at 3D CISS imaging. Sixteen (89%) of 18 patients with symptoms related to the maxillary division had NVC at the medial site of the REZ, while 16 (76%) of 21 patients with symptoms related to the mandibular division had NVC at the lateral site (P <.001, chi2 test). CONCLUSION: 3D CISS MR imaging with MPR is useful in the detection of NVC in patients with trigeminal neuralgia, compared with MR angiography. A close relationship was found between the region of neuralgic manifestation and the site of trigeminal nerve compression.  相似文献   
53.
We sequenced all 13 exons of the CYP3A4 gene derived from 48 Japanese subjects. One subject possess the 20070 T>C mutation in the exon 10 (result in leu293Pro substitution, namely CYP3A4(*)18), as heterozygote. Thus, we investigated the frequency of CYP3A4(*)18 in 118 Japanese population using polymerase chain reaction-restriction fragment length polymorphism with Msp I and determined that the frequency of the CYP3A4(*)18 allele was 1.3%.  相似文献   
54.
55.
PURPOSE: This study was undertaken to clarify the usefulness and problems involved in the clinical path of transurethral prostatectomy (TUR-P) in hospital. PATIENTS AND METHODS: The subjects consisted of 50 patients, for whom the Department of Urology, Jikei Medical University Hospital introduced its own clinical path and performed TUR-P during a period of 9 months from July 1999 to March 2000. The mean length of hospital stay, rate of postoperative complications, and the medical insurance claims made by these patients were clarified and compared with those of 73 patients before introduction of the clinical path. RESULTS: With the introduction of the clinical path, the length of hospital stay decreased by an average of 3.4 days and the total medical insurance claims decreased by an average of 18.5%. The rate of postoperative complications before and after introduction was almost equal. CONCLUSION: Our clinical path for TUR-P was well accepted by both patients and comedicals. However, the present medical treatment system in Japan is not as yet prepared to promote the introduction of this clinical path, and it will take some time before this clinical path is introduced on a full scale.  相似文献   
56.
We report a patient showing a complete remission after combination chemotherapy with nedaplatin and 5-fluorouracil (5-FU). A 63-year-old man was admitted to our hospital for advanced carcinoma of gingiva. 5-FU was administered at a dose of 1,000 mg/body (700 mg/m2) by continuous infusion for 120 hours on days 1 to 5. Nedaplatin was administered at a dose of 140 mg/body (90 mg/m2) by drip infusion for 120 minutes on day 5. This combination chemotherapy resulted in a complete remission of the tumor after 2 weeks. There has been no sign of recurrence for 6 months after the chemotherapy.  相似文献   
57.
58.
Biliary secretion of bile acids and phospholipids, both of which are essential components of biliary micelles, are mediated by the bile salt export pump (BSEP/ABCB11) and multidrug resistance 3 P-glycoprotein (MDR3/ABCB4), respectively, and their genetic dysfunction leads to the acquisition of severe cholestatic diseases. In the present study, we found two patients with itraconazole (ITZ)-induced cholestatic liver injury with markedly high serum ITZ concentrations. To characterize the effect of ITZ on bile formation in vivo, biliary bile acids and phospholipids were analyzed in ITZ-treated rats, and it was revealed that biliary phospholipids, rather than bile acids, were drastically reduced in the presence of clinically relevant concentrations of ITZ. Moreover, by using MDR3-expressing LLC-PK1 cells, we found that MDR3-mediated efflux of [1?C]phosphatidylcholine was significantly reduced by ITZ. In contrast, BSEP-mediated transport of [3H]taurocholate was not significantly affected by ITZ, which is consistent with our in vivo observations. In conclusion, this study suggests the involvement of the inhibition of MDR3-mediated biliary phospholipids secretion in ITZ-induced cholestasis. Our approach may be useful for analyzing mechanisms of drug-induced cholestasis and evaluating the cholestatic potential of clinically used drugs and drug candidates.  相似文献   
59.
Objectives  This study was performed to investigate patterns of cohabitation with farm animals in urban households in Vientiane, Lao People’s Democratic Republic, with regard to animal-to-human disease transmission. We also investigated the association between participation in hygiene-related educational activities and good hygiene practices in households with or without cohabitation with animals. Methods  A survey regarding cohabitation with animals, socioeconomic characteristics and participation in educational activities was conducted among 1,497 households randomly sampled from urban districts of Vientiane in 2001. Rates of satisfactory performance of recommended good hygiene practices according to a program commencing in 1996 were compared among households cohabiting with animals with or without participation in educational activities (reference group). Results  Even among households not engaged in agriculture as a major source of income, 54.4, 34.9, 7.9, 3.1 and 35.7% cohabited with chickens, ducks, cattle, buffaloes and dogs, respectively. The percentage of households fulfilling the recommendations for good hygiene practices was 56.7%. The rates of satisfactory hygiene practices among households participating in health education and cohabitating with chickens, ducks or cattle were greater than those in the reference group (OR = 1.7, 95%CI = 1.2, 2.3; OR = 2.0, 95%CI = 1.3, 3.0; OR = 2.3, 95%CI = 1.0, 4.9) regardless of socioeconomic factors. Households cohabiting with animals showed poorer rates of satisfactory hygiene practices than those without animals. Conclusions  Cohabitation with farm animals is common in urban Vientiane regardless of household involvement in agriculture. Further effort is required to improve hygiene conditions, despite some positive effects of health education even in households cohabiting with animals.  相似文献   
60.
We investigated the effectiveness of fosfomycin combined with other antibiotics, such as piperacillin, cefepime, ceftazidime, imipenem, meropenem, aztreonam, gentamicin, or levofloxacin, against 30 Pseudomonas aeruginosa strains, including multidrug-resistant strains, isolated from clinical specimens, using the efficacy time index (ETI) assay. The assay refers to the result of pharmacokinetics obtained from adult men volunteers, and yields an ETI to evaluate the effect of a combination of antimicrobial agents. With the ETI, based on serum concentration 3 h after the administration of two antimicrobial agents, the effectiveness of antimicrobial combinations was evaluated as follows: poor, ETI < 0.5; fair, 0.5 ≤ ETI < 1; good, 1 ≤ ETI < 8; and excellent, ETI ≥ 8. The combination of fosfomycin and cefepime (efficacy rate [excellent plus good], 76.7%) and fosfomycin/aztreonam (efficacy rate, 76.7%) appeared to be the most effective, followed by fosfomycin/meropenem (efficacy rate, 76.6%), fosfomycin/imipenem (efficacy rate, 73.3%), fosfomycin/ceftazidime (efficacy rate, 70%), fosfomycin/gentamicin (efficacy rate, 70%), fosfomycin/piperacillin (efficacy rate, 66.7%), and fosfomycin/levofloxacin (efficacy rate, 66.7%). Fosfomycin/cefepime, fosfomycin/aztreonam, and fosfomycin/meropenem may be clinically useful in selected patients, particularly for P. aeruginosa. The ETI assay provided information on the minimum inhibitory concentration (MIC) of many pairs of combined antimicrobial agents simultaneously. The ETI assay may be a useful technique with which to investigate the effect of combinations of antimicrobial agents against P. aeruginosa, including multidrug-resistant strains. Received: July 5, 2001 / Accepted: October 29, 2001  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号